Crows are far from bird-brained and have been shown to use tools to solve complex problems that baffle five-year-old children.

Now researchers have revealed that, like humans, the birds store their tools when they don’t need them, sometimes even in 'toolboxes' so they can re-use helpful implements.

New Caledonian crows, which are famous for using stick tools to extract insects from tree holes and other hiding places, also keep their tools under their feet - especially when they are perched in treetops. The creatures hold tools in their bills when foraging, but need to put them down to eat.

‘We were really excited when we saw crows in our study site carefully placing tools under their feet, to use them again later,’ said Barbara Klump, lead author of the study, published in the Proceedings of the Royal Society. They observed that crows look after their tools more carefully when foraging at height than on the ground.

‘This makes perfect sense because the higher up you are, the more challenging it would be to recover a tool,’ she explained. ‘In fact, wild crows seem to get really upset when they accidentally drop their tools.’Source